1. Technical Field of the Invention
The present invention relates to microelectronics, especially to integrated circuits comprising photodiodes.
2. Description of Related Art
Image sensors based on semiconductor components rely on the principle of converting photons into electron/hole pairs in silicon. More precisely, the charges created in the photosensitive regions are stored in the photodiode and then read by an electronic system. This electronic system, which controls the photodiode, includes in particular a transfer transistor permitting the charges stored in the photodiode to be transferred.
“Imager” technologies are sensitive to parasitic photodiode currents generated during conversion of the optical information into electrical information. In particular, there is a parasitic current called dark current, which is transferred by the read transistors when the photodiodes are not illuminated. This is characteristic of the sensitivities at low luminance of optical sensors based on CMOS technology.
However, to improve the resolution of the image taken, the dark current must be as low as possible.
There is a need to provide a solution to this problem.